Very high output (VHO) fluorescent lamp systems provide efficient, high lumen output, and good color rendering. A VHO fluorescent lamp includes an electrode at each end of a fluorescent tube, however, the electrodes substantially limit the life of a typical VHO fluorescent lamp. Another type of lamp system is an electrodeless gas discharge lamp system which includes an inductively coupled fluorescent lamp and a high frequency ballast. Electrodeless gas discharge lamp systems use electromagnetic induction instead of an electrode at each end of a fluorescent tube. Since the electrodeless gas discharge lamps do not include electrodes, the electrodeless gas discharge lamps provide many of the same benefits as the VHO fluorescent lamp systems while additionally providing a longer lamp life.
Multiple electrodeless gas discharge lamps are commonly used to illuminate a single location. A single high frequency ballast is typically used to power each electrodeless gas discharge lamp.